Well, if you have a better system, you can add the Gamecube and 3DS Emulators manually (if they don't already come with RetroArch). And ROMs are also free, just be sure to use a site which doesn't use shady tricks (such as giving you a program which, if you don't watch out, installs adware while downloading the ROMs). But the-eye.eu is a site you can trust (they even show you a wget command, with which you can download all ROMs for the chosen console automatically).
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